Fire alarm unit



June 25, 1963 R. w. FULLER FIRE ALARM UNIT Filed Aug. 24, 1960 QINVENTOR.

Russa L w. f-UL 5R 1 3,095,556 FIRE ALARM UNIT Russell W. Fuller, 503Allegheny St., Jersey Shore, Pa. Filed Aug. 24, 1960, ser. No. 51,706 1Claim. (Cl. 340-227) This invention relates to alarm devices and moreparticularly to a tire alarm wherein `a fusible member is employed tocomplete an electrical circuit to `the alarm device, and it consists inthe constructions, :arrangements and combinations herein described andclaimed.

More specifically, it is an object of the invention to provide an alarmunit, which can be manufactured and sold -at a low cost, the unitcomprising a housing for enclosing an 'ala-rm device and a dry cell, thelatter being in electrical circuit with the alarm device and va fuseblock located exteriorly of the housing to expose a fuse mounted in theblock to temperatures exteriorly `of the housing, the fuse including amember of non-conducting material which is lfusible by :an excessivegeneration of heat in proximity of the fuse to effect energization ofthe alarm.

Another important object of the invention is the provision of a fusemember of simple construction embodying but few parts, one of which is afusible member, which normally maintains the circuit to the alarm in adormant or inoperative relation with respect to a source of current.

Additional objects, advantages and features of invention will beapparent from the ollowing description considered in conjunction `withthe accompanying drawing, wherein- FIGURE 1 is a perspective view of thealarm unit, constructed in accordance with the invention.

FIGURE 2 is a sectional view taken on the line 2-2 of FIGURE 1.

FIGURE 3 is a vertical section taken on the line 3-3 of FIGURE 2.

FIGURE 4 is a perspective view of the fusible element of the unit.

FIGURE 5 is an enlarged longitudinal section taken on line 5 5 of FIGURE4.

FIGURE 6 is an exploded View, in perspective, of the elementsconstituting the fuse.

Referring more particularly to the drawing, there is illustrated analarm unit generally indicated by the refer ence character 1G, which asbest seen in FIGURES l and 3 comprises a rectangular metalli-c basemember 11 having a circumscribing wall 12, to one wall of which there ishingedly connected as at 13, a metallic housing 14. The housing is of adepth to enclose and support -a dry cell as will be now described,reference being made particularly to FIGURES 2 and 3. An end wall 16 ofthe housing is formed with la pair of spaced openings 17 for receptionof a binding post 118i and 18 respectively, which posts are insulatedfrom the Wall 16 as indicated at 19 and `19", the insulation 19' beingof a length to extend a distance along a side wall 2t) of the housingand against which a spring contact 21 rnay seat and is secured thereto,as well as the wall 20 by means of a suitable rivet 22. A similar springcontact 21' is secured to the opposed wall 20 of the housing and is indirect contact with the wall.

The binding posts 18 and 18' also serve to secure respective U-shapedclips 23, the latter being provided with opposed arms 24 between which afusible cartridge 25 may be installed.

As -a protective means for the cartridge 25 and clips 23, a ventilatedcasing or housing 26 is provided and is secured to the wall 16 byfrictional fit upon the insulation strip 19 or otherwise.

rates Aarent Within the housing at the end opposite the wall 16 an alarmdevice 27 is secured by means of a bracket 28 which is mounted upon thebase 11 and as best seen in FIGURES l and 3, the housing 14 is providedwith a perforated disk 29, whereby sounds from the 'alarm may beemitted.

'Ihe alarm device 27 here shown is of the siren type, although anelectrical operating bell may be employed, if desired. The circuitbetween the battery 15 and alarm device is by way of a wire 30 connectedto a contact 31 of the siren and the binding post 18'; the circuit beingcompleted through the grounded clip 21.

A suitable catch 32 may be employed to retain the housing 14 in closedrelation with the base 11.

The fusible cartridge 25 is shown in detail in FIGURES 4, 5 and 6 andcomprises an elongated cylindrical housing 33 of fiber material, theopen ends of which are closed by a metallic cap 34. Enclosed within thecylindrical housing 33 there is a helical spring 35 one end of which isin contacting relation with the adjacent cap 34, the opposite end beingin pressure engaging contact with a non-metallic fusible cartridge 36,which as shown in FIGURE 5, maintains the spring 35 in spaced relationwith the adjacent end cap 34.

vIn use, the alarm unit 10 may be suspended in the most likely locationfor a 4lire occurrence, by means of a hanger 37. In the event of a lire,the heat therefrom will liquify the cartridge 36 and pressure exerted bythe spring 35, which -is under compression will be such as to hastendisintegration and liquiiication of the cartridge to an extent that thespring will be in contact-ing relation between the two caps 34,whereupon the alarm will be energized. In order to restore the alarm forfurther protective use, it is only necessary to install a new cartridge.

While I have shown and described a preferred construction of alarm unit,this is by way of illustration only, and I consider as my own tall suchmodifications in construction as fairly fall within the scope of theappended claim.

I claim:

A lire alarm unit comprising a rectangular metallic base member having acircumscribing wall, a metallic housing hingedly connected to said wall,a dry cell positioned in said housing, an alarm device afiixed to saidbase member and said alarm device Iadapted to be received in saidhousing when the housing and base member are in closed relation withrespect to each other, an end Wall of said housing being provided with apair of spaced apart openings, a pair of binding posts extending throughsaid openings, said posts being insulated from ysaid end wall by meansof insulation which is of a 'length to extend a distance along `a sidewall of the housing, a first spring Contact arranged in said housingland abutting the portion of the insulation contiguous to the side wallof the housing, a securing element connecting said spring contact to theside wall of the housing, a second spring contact secured to the opposedside wall of the housing and arranged in direct contact with the lastnamed side wall, and said spring contacts engaging opposite end portionsof the dry cell, U-shaped clip members connected to said binding postsand arranged exteriorly of said housing, and said clip members beingarranged in spaced aligned relation for receiving a cartridge having afusible element normally maintaining an open circuit to said alarmdevice, a ventilated casing arranged exteriorly of said housing andsurrounding said cartridge, said housing being provided with aperforated disk for alignment with the alarm device whenthe housing andbase member are in closed relation with respect to each other, saidalarm device including a contact, and a conductor electricallyconnecting said contact to one of said binding posts.

References Cited in the le of this patent UNITED STATES PATENTS 573,903McGahy Dec. 29, 1896 581,544 Enholm Apr. 27, 1897 1,199,050 Cid Sept.26, 1916 Bunten Nov. 22, 1932 Wood Oct. 1, 1935 Gogniat May 10, 1949Shaw July 11, 1950 Sloan Dec. 25, 1956 Miller Feb. 4, 1958 Pvetz Apr.29, 1958 Massar Apr. 26, 1960

